1,721,066 research outputs found
Hyperprolactinemia induces a decrease of beta-endorphinergic activity in the hypothalamus
Going Beyond Counting First Authors in Author Co-citation Analysis
The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Regulation of immune functions in rat splenocytes after acute and chronic in vivo treatment with CP-55,940, a synthetic cannabinoid compound.
Mainly mu-opiate receptors are involved in luteinizing hormone and prolactin secretion
We evaluated plasma PRL and LH concentrations in the rat after the administration of drugs that exert a specificity directed mainly, although not absolutely, toward the mu-, delta-, or kappa-opiate receptors, in order to investigate the role of different receptors and thus the respective endogenous ligands in the modulation of the release of these anterior pituitary hormones. LH concentrations were evaluated in prepuberal female rats, in adult male rats, and in ovariectomized, estradiol benzoate-treated rats. PRL concentrations were evaluated in suckling rats, in ovariectomized, estradiol benzoate-treated rats, and in ether-stressed rats. The delta-antagonist ICI 154129 never affected PRL or LH concentrations, whereas both the mu- and kappa-antagonists, naloxone and MR 1452, respectively, seemed to be effective. However, when graded doses of the two classes of antagonists were tested, the mu-antagonist appeared to be effective on both hormones at doses that were one tenth of those of the kappa-antagonist. In conclusion, the mu-receptor seems to be the most profoundly involved in the regulation of PRL and LH secretion
Mainly mu-opiate receptors are involved in luteinizing hormone and prolactin secretion.
We evaluated plasma PRL and LH concentrations in the rat after the administration of drugs that exert a specificity directed mainly, although not absolutely, toward the mu-, delta-, or kappa-opiate receptors, in order to investigate the role of different receptors and thus the respective endogenous ligands in the modulation of the release of these anterior pituitary hormones. LH concentrations were evaluated in prepuberal female rats, in adult male rats, and in ovariectomized, estradiol benzoate-treated rats. PRL concentrations were evaluated in suckling rats, in ovariectomized, estradiol benzoate-treated rats, and in ether-stressed rats. The delta-antagonist ICI 154129 never affected PRL or LH concentrations, whereas both the mu- and kappa-antagonists, naloxone and MR 1452, respectively, seemed to be effective. However, when graded doses of the two classes of antagonists were tested, the mu-antagonist appeared to be effective on both hormones at doses that were one tenth of those of the kappa-antagonist. In conclusion, the mu-receptor seems to be the most profoundly involved in the regulation of PRL and LH secretion
Sex-related effects on behaviour and ß-endorphin of different intensities of formalin pain in rats.
The effects of two intensities of formalin pain on behaviour and beta-Endorphin (beta-EP) concentration in the brain and pituitary were studied in male and female rats. The animals were familiarized with the Hole-Board apparatus for 3 days, and then, after a subcutaneous injection of formalin (50 mu l, 0.1 or 10%) or Sham-injection (Control) in the hindpaw, they were tested in the Hole-Board for 60 min. Licking, Flexing and Paw-Jerk of the injected limb were recorded. beta-EP concentration was determined in the hypothalamus (HYP), the periaqueductal gray matter (PAG), the anterior pituitary (AP) and the neurointermediate lobe (NIL). Licking and Flexing durations were greater in females than males only with formalin 10%. Sex differences in beta-EP concentration between the Control groups were found in all tissues except the HYP; beta-EP levels were higher in females in the PAG and NIL, but greater in the AP in males. beta-EP concentration increased in males in the HYP and NIL with formalin 10%; in females, a decrease was found in the HYP with formalin 0.1%. The present results suggest that: (a) there are differences between males and females in the responses to formalin pain, and the nature (pattern and duration) of the sex differences varies according to the pain intensity; (b) there are differences in beta-EP concentration between the two sexes in control animals, and male and female rats also exhibit differences in the modifications of beta-EP in response to formalin-induced pain
Variations on the Author
“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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